Thermostatically controlled variable speed device



p 1938. D. H. MOGOGY 2,129,066

THERMOSTATICALLY CONTROLLED VARIABLE SPEED DEViCE Filed June 2, 1936 4 Sheets-Sheet 1 a 2 d l E E I 4 J E 2 9 17/06/7751? Fo/M/v/ flflfay v- Sept. 6, 1938. D H. M GOGY THERMOSTATICALLY CONTROLLED VARIABLE SPEED DEVICE Filed June 2, 1936 4 Sheets-Sheet 2 IIIIIIIIIIIIIIIIIM d /TIIIIIIII 2'1 i ME I J 17100? 75}- /m/d MWfoyy Sept. 6, 1938. D. H. McGOGY 2,129,066

THERMOSTATICALLY CONTROLLED VARIABLE SPEED DEVICE Filed June 2, l956 4 Sheets-Sheet 3 Sept. 6, 1938. D. H. MCGOGY 2,129,066

THERMOSTATICALLY CONTROLLED VARIABLE SPEED DEVICE Filed June 2, 1956 4 Sheefl s-Sheet 4 I I Z I I 25 I Z 22 Patented Sept. 1938- UNITED STATES ;PATENT orrlca 2,129,066 THEBMOSTATICAILY CONTROLLED VARI- ABLE SPEED DEVICE. DonaldH. McGogy, McMinnville, Oreg. Application June 2, 1936, Serial No. 83,085 1 Claim. (01. 74-113) to providecorrection means to eliminate inaccuracies occasioned by temperature variations.

It is well known that variations in temperature cause variations in volume and density of fluids; that, for instance, the volume of oil, gasoline,

etc., expands with heat, the amount of expansion difiering with different fluids. Thus in the handling of large volumes of oil or gasoline it is customary, after measuring actual volume, to figure correction based on mathematical, caicula tion according to the temperature.

The principal object of my invention is to provide a thermostatically controlled variable speed device for adjusting'the speed of operation of the registering mechanism of a fluid meter which will permit such mechanism to be speeded up or retarded to correspond with temperature variations in the fluid being metered; whereby, with the passage of fluid thru a meter of flxed volume. the registering mecha relation to the meter for higher temperatures and more rapidly in relation to the meter at lower temperatures, and thus cause the equivalent of a standard measure at a predetermined mean temperature to be accurately delivered regardless of temperature variations.

Another object of my invention is to provide an adjustment mechanism of the type indicated in such form as to be suitable as an attachment for standard types of fluid meters now in use, thus making it unnecessary to build special meters for the utilization of my correcting device.

Another object of my invention is to provide such a device which will be simple, durable and comparatively low in cost.

Another object is to provide such a device which can be accommodated to a wide range of temperature and particularly to very high temperatures for use in measuring fluids in chemical manufacturing plants, refineries, etc. I

These and other objects I attain by constructing and employing my variable speed device in the manner now to be described with reference to the accompanying drawings, in which:

Fig. 1 shows a side elevation of my device con nected to a meter and to the pipe through which the metered fluid flows, the drawings being more or less diagrammatic, with parts broken away and shown .in section; v

Fig. 2 (Sheet 2) shows a vertical longitudinal section through the center of my device taken 111 will move more slowly in approximately on the lines 2-2 of Figs. 3 and 4, with certain parts broken away;

Fig. 3 (Sheet 2) is a bottom plan view with the lower portion of the housing of my device removed in order to show the arrangement of the mechanism of my device as viewed from the bottom; e 1

Fig. 4 (Sheet 3) shows a horizontal section taken on the line 4-4 of Fig. 2 looking down, and shows a top plan view of the interior mechanism corresponding to the bottom plan view of Fig. 3;

Fig. 5 (Sheet 2), shows a vertical transverse section on the line 5-5 of Fig; 2, looking in the direction indicated by the arrows;

Fig. 6 (Sheet 3) shows a bottom plan view similar to Fig. 3, but with part of the interior mechanism removed to show the thermostatic element more clearly, and with a portion of the housing about the thermostatic element broken away; Fig. 7 (Sheet 3) shows a fragmentary detail of the thermostatic element shown in Fig. 6, and illustrates by broken lines the action of the thermostatic element under temperature changes;

Fig} 8 (Sheet 3) shows a fragmentary bottom, plan view of a portion of the interior of my device corresponding to Fig. 3 but with the thermostatic element moved to the position indicated by the broken lines in Fig. '7, thus showing the eflect of a change of position of the thermostatic element on the working of the mechanism composing my device:

view of one of the pawls of the groups of multiple pawls used in my device;

Fig. 10 (Sheet 4) shows a top view of one of the said groups of pawls;

Fig. 11 (Sheet 2) shows a sectional view of a modification of the means of anchoring the end of the bi-metallic thermostatic strip used in my device;

Fig. 12 (Sheet 2) shows a transverse section on the line l2--l2 of Fig. 11; and

Fig. 13 (Sheet 4) shows a fragmentary vertical longitudinal section taken on the same line as the section shown by Fig. 2, but drawn on a larger scale than Fig. 2 to indicatev the individual elements more clearly.

Referring first to Fig. 1, a indicates the pipe through which the fluid being metered passes, and 1) indicates a standard meter, such as at present used for metering fluids or liquids. The passage of the fluid through the meter b causes a vertical shaft 0, included in the meter, to be rotated. The shaft 0 is connected, through the meregistering apparatus (such with the flow of the fluid through pipe a, a portion of the fluid will constantly be drawn through extending part way. around the track and idly mounted by means of set screw 20.

my device by a suction action, as indicated by the arrows in Fig. 1. My device and the connecting pipes o and h are preferably covered with suitable insulation, indicated in section by i, to insure that the portion of the metered fluid passing through my device will be at the same temperature as that passing through pipe (2.

Referring now to Figs. 1, 2 and 5, my device, designated by d, is enclosed in a housing comprising an upper section and a bottom plate 2 which is bolted to the upper section; a tight seal between the. two sections being obtained by means of the gasket 2a. The upper section I has an elongate lateral portion 3 to accommodate the stem of the bi-metallic thermostatic strip 4 which is an important element in my invention.

The bottom plate 2 of the housing is made with an external; centrally located gland 5 through which the shaft 6 of the meter extends. The gla'nd has standard packing gland elements 6 and 1, and the lower end of the gland 5 has threaded thereon an adjustable cap 8, which serves to hold the l in place.

The upper section I of packing glandelements 6 and the housing is provided with a .gland 9 through which the vertical shaft l extends, which shaft is connected to the registering apparatus e. The gland 9, similarly to gland 5, is provided with packing gland elements, and a cap The registering apparatus e is secured by suitable means to the top of my device, as indicated in Figs. 1 and 2.

Within the housing section a circular track I2 is rigidly attached concentric with the axis of rotation of shaft 0 (see Figs. 2; 3, 4 and 5). This circular track |2 has a slot along its median line adapted to accommodate a'sliding plate or bridge l3. The inner edge |4 of this sliding bridge I3 constitutes an arc of greater radius than that of the circular track l2 and provides an adjustable cam surface. The ends of-the sliding bridge l3 are attached to a U-shaped horizontally sliding mem-' her or yoke l5 having a lug 15b adapted to slide in a slot provided inthe circular track 2, the ends of the sliding bridge I 3 being connected to the yoke I5 by means of spacers I511. The outer edge of the sliding bridge I3 is provided with an ear l6 having a vertical stud I1. On the upper endoi' this stud IT a slide block I8 is pivotally mounted, which block bears in a slotted pivoted cam arm 34, later described.

On the meter shaft 0 a 4-arm spider I9 is rig- Above the spider |9 are rotatably mounted, on the shaft 0, a pair of lower cross-arms 2 I, a ratchet wheel 22, and a second pair of upper cross-arms 23, respectively. (See Figs. 3, 4 and 13.) The two cross-arms 2| cross each other approin'mately at right angles but may be given partial rotation independent of each other on the shaft 0. The ends of the lower and upper cross-arms 2| and 23, respectively extending below and above the ratchet wheel 22 are secured together by means of shouldered pins 24, the two cross-arms 23 corresponding to and being arranged similarly to the cross-arms 2|. The cross-arms 2| and 23 6 and 7.- The outer end Each of the arms of the spider l9 has connected to its outer end a pivoted link 21, which link in turn is pivotally connected to one of the pairs of links 25, and a roller 28 mounted between said links. The. rollers 28 travel on the inner surface of thecircular track 2, and the inner edge I4 of the slidable bridge l3. Leaf springs 29 are provided between the spider 9 and the lower pair of cross-arms 2|, as shown in Fig. 3, by which leaf springs the rollers 28 are held under tension against the circular track l2 and bridge I3.

Each of the groups of pawls 23 is made up of individual pawls of difierent lengths, as shown more clearly in Fig. 10 (Sheet 4) so that one of the pawls of each group will always engage one of the teeth of the ratchet wheel 22. Providing several pawls of different lengths accomplishes the same result as having finer teeth on the perimeter of ratchet wheel 22, but is more practical. Springs 30 (see Figs. 9 and 10) hold the pawls against the ratchet wheel 22. e

As apparent from Fig. 3, when the inner cam edge i 4 of the slidingbridge |3 does not project beyond the inner surface of circular track l2, the rotation of spider |9 will cause the rollers 28 to travel around on the track l2, thus causing the ratchet wheel 22 to be rotated at the same speed as the spider l9; one of the pawls 26 of each of the four groups of pawls engaglngjthe teethof the ratchet wheel 22. But when the cam edge l4 of the sliding bridge l3. projects beyond the inner surface of the track l2, as shown in Fig. 3, then each roller 28, as it comes into contact with the cam edge I 4 of the bridge l3, will be forced inward toward the common axis of rotation of spider l9, ratchet wheel 22, and lower and upper cross-arms 2| and 23, and such inward movement of the rollers 23, by increasing the angle'between the connecting links and 21, will cause the'respective cross-arms 2| and 23 to be moved ahead of the corresponding arm of spider I9; and the pawls carried by the ends of said cross-arms will in turn move ratchet wheel 22 slightly ahead. This occurs repeatedly as each roller. 28 passes over the cam edge l4 of the bridge I3; and the amount-of such increments in speed of rotation given to the ratchet wheel 22, in comparison with the speed of rotation of spider l9, will depend upon the extent to which the cam edge l4 of bridge l3 projects beyond the inner surface of circular track l2. Thus by adjustment of sliding bridge l3, ratchetwheel 22 can be caused to rotate at the same speed as spider I9, or'at a greater speed than spider |9.

On the upper hub of ratchet wheel 22 is rigidly mounted a. gear 30a (see Fig. 13, Sheet 4), meshing with a gear 3| rigidly mounted on the shaft I0 oi the registering apparatus e. Thus the rotation of ratchet wheel 22 causes the rotation of the shaft 0, and the operation of the registering apparatus e.

The upper end of shaft 0 is journaled in a,

sleevebearing 32 mounted in a socket 33 on the interior of housing The sleeve bearing 32 is made withannular flange 35, and below said flange the cam arm 34 is rotatably mounted on the sleeve bearing 32. (See Figs. 2 and 13.) The cam arm 34 is shown more clearly in Figs. 4, of said cam arm 34 has a curved head provided with a slot 34a in which .bears the slide block 53; the curvature of slot 34a being such that movement of the cam arm 34 will cause the slide block I8, and with it the bridge II, to be moved lineally in and out, with respect to axis of rotation of the shaft 0. A pivoted link 36 connects cam arm 34 to the free end of the bimetallic thermostatic strip 4. The other end of the thermostatic strip 4 .is anchored in the outer end of the elongate section 3 of the housing i of my device. (See Figs. 2 and 6.) Temperature changes of the fluid passing thru pipe g into the housing of my device, and thence out thru pipe h will cause changes in the curvature of the bi metallic thermostatic strip 4, and such change in the curvature of strip 4 will cause a movement of the cam arm 34, which in turn will cause a change in the position of sliding bridge I! in the manner already explained.

The operation of my device is as follows: For convenience, for ordinary purposes, I make the gear II with 4% more teeth than the gear 30a with which it meshes; that is to say, the meshing gears 30a and -3l are so arranged that shaft iii of the registering mechanism e will be rotated at 4% less speed than ratchet wheel 22. when taking 60 F. as the standard mean temperature at which the fluid is to be metered, the bi-metallic thermostatic strip 4 and the connecting parts are so set that the position of the cam arm 34 and sliding bridge is will cause the ratchet wheel 22 to be driven with a speed increment approximately 4% greater than the spider l9, and meter shaft e. Thus at 60 F. temperature the shaft and the shaft l0 would be rotated at approximately the same speed, since the increment in speed of the ratchet wheel 22 at that temperature will be exactly offset by the loss in speed between gears 30a and 3 l The thermostatic strip 4 at lower temperatures will then cause the sliding bridge ii to be projected further into the inner surface of track l2; and similarly, higher temperatures than 60 F. will cause the bridge I! to be moved outward until, at the highest temperature for which my device would make corrections, the bridge l3 will no longer project into the track I! at all. In other words, as the temperature of the fluid passing thru my device rises above 60 F., the speed of shaft III with relation to that of shaft c will be decreased, and as the temperature of the metered fluid falls below 60 F. the speed of shaft Ii) will be increased. Thus an automatic micrometer adjustment of the registering device e is obtained corresponding with the temperature fiuctuation of the fluid being metered. Due to the very slight load imposed upon the bi-metallic thermostatic strip 4, and to the fine adjustments made possible by the multiple pawl elements, a very high degree of accuracy is obtainable for even slight fluctuations in temperature.

While I have described my device as being set for a mean temperature of 60 F., it is obvious that it could be set for any other mean temperature by altering the anchored position of the thermostatic strip 4, and, furthermore, that the range of temperature covered can be altered by changing the composition and form of my thermostatic strip. For ordinary purposes, however, I have found that a standard type of bi-metallic thermostatic strip, which is readily obtainable, produces satisfactory results and is suitable for ordinary use in my device as described.

Figs. 2 and 6 show the means by which the bimetallic thermostatic strip 4 is anchored in the end of the elongate housing section 3. A wedgeshaped block 31 holds the end of the strip 4 firmly against the abutment 38 of one of the converging walls of the housing, and the block 31 is held in position by means of -a screw!!- passing through an end'plate 40 which rests on shoulders provided in a recess of the housing walls. Figs. 11 and 12 show a modified means of attaching the end of a thermostatic strip 4. In the modified construction illustrated in these figures, a block 4! is pivotally supported in the housing walls by a pin 42. The end of the thermostatic strip 4 is inserted in a slot in block 4i, and is clamped therein by means of a screw 43. The position of the block 4|, and therewith the position of the end of the thermostatic strip 4, is determined by two screws 44 and 45 extending thru a plate at the end of the housing. 'Iightening one of these two screws and loosening the other will cause the block 4| to be tilted on pin 42. This modified means of supporting the thermostatic strip 4 is particularly convenient in cases where my device is to be used for difierent mean temperatures, for example, in chemical manufacturing plants where different fluids are to be metered and temperature corrections made in the metering on the basis of different mean temperatures. This means could also be used in place of the manual adjustment means provided in fiuid meters.

I claim:

In a variable speed transmission of the type described having a rotating shaft, an arm rigidly mounted on said shaft, a second arm rotatabiy mounted on said shaft, articulated links connecting the extremities of said arms, a ratchet wheel mounted on said shaft and a pawl carried by said second arm engaging said ratchet wheel, a stationary curved track concentric with said shaft, a guide roller carried by said links and adapted to roll on said track, a slot in said track, a slidable bridge located in said slot, the inner edge of said bridge constituting an arc of greater radius than said track, thereby providing a cam surface when said bridge is projected within said track, and thermostatically controlled means for positioning said bridge and therewith said cam surface.

DONALD H. MCGOGY. 

